did u read the supported linux distros on the softether website??
[glow=red,2,300]Red Hat Enterprise Linux
and whonix is based on debian (im sure u have read that more than 10 times before u reached here)
also since we r friends in noobness (im a user and u r a user) i would prefer to read
“How To Ask Questions The Smart Way”.
(im sure u gonna benefits from the advises there and dont look at the name of it because ur question is not stupid but its not for whonix to solve)
also my other advise would be regarding softether, it dont advise u to use it but use another one because its vpn servers r 2 far away (japan and korea) and its highly not recommended with tor because i used it on my windows pc with tor and the software turned off and on more than usual vpn do when browsing.
alternatives => openvpn (its also free)
but b4 even using vpn ,the question who u r hiding urself from ? from gov. or its general anonymity ? did u know also the vpn turned off and on while u r browsing (its general problem for all vpns) ? (the solvation of this problem u need to use netcat with vpn)
i know it sound u need to get many articles to read and stuff to do in order to get the sufficient anonymity while using vpn. but that is the truth nothing come without tiredness
thnx for asking whonix , feel free to ask more (but read the article b4 u ask ).
have a good day (f)